Performance evaluation of multicarrier PWM methods for cascaded H-bridge multilevel inverter

Multilevel inverters are becoming more popular in field of high power energy control due to their capability for high power applications. On the other hand, they require switching control methods to generate sinusoidal output with less harmonic. This paper analyses five various multicarrier pwm methods ,namely, Phase Disposition (PD), Phase Opposition Disposition (POD) , Alternative Phase Opposition Disposition (APOD), Phase Shifted (PS) and Variable Frequency (VF). To compare the performance of these techniques with respect to the Total Harmonic Distortion (THD) and RMS value of the output voltage, they are applied to single phase five level cascaded inverter.